Apparatus for collecting liquid mercury

ABSTRACT

Apparatus for collecting spilled liquid mercury comprising a container and a pad of nonrigid, open-cell foam material for entrapping drops of spilled mercury to permit the transferring of the mercury to the container for release of the mercury therefrom for collection in the container. The pad entraps the spilled mercury when it is compressed against a surface having drops of mercury thereon and holds the mercury within the pad when it is lifted clear of the surface. A perforate plate is mounted in the container spaced above the bottom thereof so as to support the pad when the pad is pressed downwardly thereagainst to effect compression of the pad and release of the mercury entrapped within the pad. A lid is removably secured to the mouth of the container. The container&#39;&#39;s height is such that a space is provided between the perforate plate and the undersurface of the lid sufficient to permit the pad to rest in a stored position on the perforate plate without compression of the pad.

ilnite States Patent [191 Elbreder Aug. 114, 1973 APPARATUS FORCOLLECTING LIQUKD MERCURY [76] Inventor: Charles H. Elbreder, 1702 ChaseDr., Fenton, Mo. 63026 22 Filed: Nov. 29, 1971 211 Appl.No.: 202,871

[52] US. Cl. 15/1, 15/221, 15/244 R,

15/260, 294/1 [51] Int. Cl. A471 13/16, A471 13/58 [58] Field of Search15/1, 221, 244 R,

27,444 11/1910 Great Britain 15/260 Primary Examiner-Danie1 BlumAttorney-Stuart N. Senniger et al.

[57] S :1": CT

Apparatus for collecting spilled liquid mercury comprising a containerand a pad of nonrigid, open-cell foam material for entrapping drops ofspilled mercury to permit the transferring of the mercury to thecontainer for release of the mercury therefrom for collection in thecontainer. The pad entraps the spilled mercury when it is compressedagainst a surface having drops of mercury thereon and holds the mercurywithin the pad when it is lifted clear of the surface. A perforate plateis mounted in the container spaced above the bottom thereof so as tosupport the pad when the pad is pressed downwardly thereagainst toeffect compression of the pad and release of the mercury entrappedwithin the pad. A lid is removably secured to the mouth of thecontainer. The containers height is such that a space is providedbetween the perforate plate and the undersurface of the lid sufficientto permit the pad to rest in a stored position on the perforate platewithout compression of the pad.

3 Claims, 4 Drawing Figures APPARATUS FOR COLLECTING LIQUID MERCURYBACKGROUND OF THE INVENTION This invention relates to apparatus forcollecting liquid mercury from a surface, and more particularly relatesto apparatus for collecting droplets or small quantities of spilledmercury.

Among its various uses, mercury is commonly employed in dental officesfor the preparation of various dental materials and is used inscientific laboratories in various laboratory apparatus, such asmanometers and barometers. If properly stored and handled, mercury isrelatively safe material, but it does pose a serious health hazard(i.e., mercury intoxication) to persons breathing mercury vapor.Although mercury is a metal and has a relatively high boiling point (357C.), it does exhibit a tendency to vaporize in air, the equilibriumconcentration of mercury in air at 25 C. being about 2 milligrams percubic meter (mg/m Small quantities of mercury are sometimesinadvertently spilled. This spilled mercury tends to splatter uponstriking a surface (e.g., the floor) forming small droplets of liquidmercury. These small droplets expose more surface area of the mercury tothe air, thereby increasing the tendency of the liquid mercury tovaporize. If spilled mercury is not promptly collected, significantamounts of mercury I vapor may be inhaled by persons working in the areaso that over a period of time these persons may become afflicted withmercury intoxication.

Mercury collectors have been used in the past. Some of these prior artmercury collectors utilize a foam pad which is bonded to theundersurface of a threaded lid which is screwed into the mouth of thecontainer. The

pad is used to soak up the spilled mercury and to transfer it to thecontainer where the pad is compressed by threading the lid into thecontainer to effect the release of the mercury in the pad. However,these prior art mercury collectors have several disadvantages, forexample: the pad is stored within the container in a compressed statecausing the pad to develop permanent compression set which renders thepad substantially ineffective'for picking up spilled mercury; and thescrewing of the lid onto the container to compress the pad tends to tearthe pad from the lid and substantiallyincreases the time required tocollect a quantity of spilled mercury.

SUMMARY OF THE INVENTION Among the several objects of this inventionmaybe noted the provision of a mercury collector for collectingquantities of spilled mercury; the provision of such a mercury collectorin which its foam collecting pad is compressed without twisting orturning movement to effect release of the mercury entrapped within thepad; the provision of such a mercury collector in which the pad isstored within the container in an uncompressed state; and the provisionof such a mercury collector which is easy to use and which is ofeconomical construction. Other objects and features of this inventionwill be in part apparent and in part pointed out hereinafter.

Briefly, apparatus of this invention for collecting spilled liquidmercury comprises a container having an upwardly opening mouth and abottom wall. Collecting means are provided for entrapping drops ofspilled mercury thus permitting the transferring of the mercury to thecontainer for release of the mercury from the collecting means forcollection in the container. This collecting means comprises a pad ofnonrigid, open-cell foam material which when compressed against asurface having drops of mercury thereon permits the spilled mercury toflow into the cells of the pad and which when uncompressed holds themercury within the pad. A perforate plate is mounted within thecontainer spaced above the bottom wall thereof so as to support thecollecting means when the latter is pressed downwardly thereon tocompress the pad which releases the mercury entrapped in the pad andpermits the mercury to flow through the holes in the plate forcollection in the bottom of the container. A lid is removably secured tothe mouth of the container, and the container is of a height to providea space between the plate and the lid sufficient to permit thecollecting means to rest in a stored position on the plate withoutsubstantial compression of the pad when the lid is secured to the mouthof the container.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of apparatus ofthis invention with parts broken away showing collecting means restingin a stored position on a perforate plate disposed within a container;

FIG. 2 is a vertical section on line 22 of FIG. 1 showing the collectingmeans in its stored position with substantially no compression of itsfoam pad;

FIG. 3 is a view similar to FIG. 2 with the lid of the container removedand with the collecting means compressed against the perforate plate torelease mercury from within the pad for collecting in the container; and

FIG. 4 is an elevation view showing the collecting means disposed abovea surface having drops of mercury thereon and showing (in phantom) thecollecting means as it is pressed down against the surface forentrapment of the mercury within the pad.

Corresponding reference characters indicate corresponding partsthroughout the several views of' the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings,apparatus of this invention for collecting spilled liquid mercury isindicated in its entirety at l and is shown to comprise a cylindricalcontainer 3 (e.g., a jar) having an upwardly opening mouth 5 (see FIG.3), a cylindrical side wall 7 and a bottom wall 9. A lid 11 isthreadably secured to the upper end of side wall 7 to seal the containermouth when the ap paratus is not in use.

A mercury collecting unit generally indicated at 13 is provided forentrapping drops of spilled liquid mercury within the collecting unitthus permitting the spilled mercury to be transferred to container 3 forcollection therein. This collecting unit includes a pad 15 of nonrigid,open-cell foam material (e.g., polyurethane foam) which when compressedagainst a surface S having drops of mercury M thereon (see FIG. 4)permits the mercury to flow into the cells of the pad and which whenuncompressed (i.e., when the pad is lifted clear of surface S) holds themercury entrapped within the pad. Pad 15 is bonded to the bottom face ofa backup member 17, the latter being a rigid backing for the pad toinsure uniform compression of the pad when it is pressed against asurface. A handle 19 is secured to and extends up from the centerportion of the backup member to facilitate holding of the collectingunits. Pad and backup [7 are circular in plan and have a loose fitwithin the container to permit easy removal of the collecting unit fromthe container and replacement therein.

A circular perforate plate 21 having a plurality of holes 23 therein ismounted in container 3 and spaced above bottom wall 9. The plate hasthree legs 25 extending downwardly from its bottom face for supportingthe plate above the bottom of the container. When collecting unit 13 ispressed downwardly against the upper surface of the perforate plate toeffect compression of pad 15, mercury entrapped within the pad isreleased from the pad to flow through holes 23 in the plate forcollection in the bottom of the container (see FIG. 3). The diameter ofthe perforate plate is somewhat smaller than the inside diameter of thecontainer thus providing a loose fit of the plate within the containerand permitting the plate to be readily removed therefrom. As shown inFIG. 2, the height of container 3 is such that a space is providedbetween the upper surface of perforate plate 21 and the undersurface oflid 11 when the lid is threaded on the upper portion of side wall 7 toclose off container mouth 5. Thus with the lid threaded in place,collecting unit 13 rests in a stored position within the container withpad 15 supported on the perforate plate without any substantialcompression. It will be noted that with the collecting unit in itsstored position, handle 19 is disposed below the lid so that pad 15supports only the weight of the collecting unit. Thus, the pad remainsin a substantially uncompressed state when it is in its stored positionto thereby avoid compression set from developing in the pad, thusmaintaining the effectiveness of the pad to pick up spilled mercury froma surface.

To use mercury collector l of this invention to collect a quantity ofliqiuid mercury which has been inadvertently spilled on a surface S, lid11 is unscrewed from container 3 and collecting unit 13 is lifted fromits stored position within the container. The collecting unit is firmlypressed against a surface S having drops of mercury M thereon tocompress the pad (as shown in phantom in FIG. 4) and thereby permit themercury to flow into the open cells of the pad. The collecting unit isthen lifted clear of surface S permitting the pad to return to itsuncompressed state for entrapping the mercury within the pad. Thecollecting unit is then moved to a position within the container and ispressed downwardly against perforate plate 21 (see FIG. 3) to effectcompression of the pad for release of the mercury entrapped therein. Asthe mercury is released from the pad, it flows through holes 23 in theperforate plate and collects in the bottom of the container. Theabove-stated procedure is repeated until all the spilled mercury hasbeen collected in the container. The collected mercury may then bepoured from container 3 into another container (not shown) for reuse orfor being reclaimed. Collecting unit 13 is then returned to its storedposition within the container and lid 11 is screwed on the container toprevent escape of vapor from any mercury that may remain in thecontainer.

lt is an important feature of mercury collector 1 of this invention thatpad 15 of collecting unit 13 is compressible against perforate plate 21simply by pressing down on handle 19 as indicated by the arrow in FIG. 3without twisting or turning the pad relative to perforate plate 21. Thedirect manner in which the pad is compressed simplifies the use of amercury collector of this invention, speeds up the collection of spilledmercury, and prevents damage of the pad.

in view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As various changes could be made in the above construction withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

I claim:

1. Apparatus for collecting spilled liquid mercury comprising:

a container having an upwardly opening mouth and a bottom wall;

collecting means for entrapping drops of spilled mercury thus permittingthe transferring of the mercury to the container for release of themercury therefrom for collection in said container, said col lectingmeans comprising a pad of nonrigid opencell foam material which whencompressed against a surface having drops of mercury thereon permits thespilled mercury to flow into the cells of said pad and which whenuncompressed holds the mercury within the pad, said collecting meansfurther including a back-up member for said pad and a handle secured toand extending up from said back-up member; perforate plate mountedwithin said container having a plurality of holes therein, said platebeing spaced above the bottom wall of the container and being adapted tosupport said collecting means when the latter is pressed downwardlythereon to compress said pad to release mercury entrapped within the padand to permit the mercury to flow through said holes in the plate forcollection in the bottom of said container; and lid removably secured tothe mouth of said container, said container being of a height to providea space between said plate and said lid sufficient to permit saidcollecting means to rest in a stored position on said plate withoutsubstantial compression of said pad when said lid is secured to themouth of said container.

2. Apparatus as set forth in claim 1 wherein said plate has a pluralityof legs extending down from its bottom surface for supporting the plateabove the bottom wall of said container.

3. Apparatus as set forth in claim 1 wherein said foam material ispolyurethane foam.

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1. Apparatus for collecting spilled liquid mercury comprising: acontainer having an upwardly opening mouth and a bottom wall; collectingmeans for entrapping drops of spilled mercury thus permitting thetransferring of the mercury to the container for release of the mercurytherefrom for collection in said container, said collecting meanscomprising a pad of nonrigid open-cell foam material which whencompressed against a surface having drops of mercury thereon permits thespilled mercury to flow into the cells of said pad and which whenuncompressed holds the mercury within the pad, said collecting meansfurther including a back-up member for said pad and a handle secured toand extending up from said back-up member; a perforate plate mountedwithin said container having a plurality of holes therein, said platebeing spaced above the bottom wall of the container and being adapted tosupport said collecting means when the latter is pressed downwardlythereon to compress said pad to release mercury entrapped within the padand to permit the mercury to flow through said holes in the plate forcollection in the bottom of said container; and a lid removably securedto the mouth of said container, said container being of a height toprovide a space between said plate and said lid sufficient to permitsaid collecting means to rest in a stored position on said plate withoutsubstantial compression of said pad when said lid is secured to themouth of said container.
 2. Apparatus as set forth in claim 1 whereinsaid plate has a plurality of legs extending down from its bottomsurface for supporting the plate above the bottom wall of saidcontainer.
 3. Apparatus as set forth in claim 1 wherein said foammaterial is polyurethane foam.